In the prior art, a lithium-ion rechargeable battery and a nickel-metal hydride rechargeable battery are each known as a rechargeable battery that is a type of a power storage device. For example, in a lithium-ion rechargeable battery, an electrode assembly, which is formed by stacking or winding positive electrode sheets and negative electrode sheets, is accommodated in a case. In the electrode assembly, the positive electrode sheets and the negative electrode sheets form a layered structure. The positive electrode sheets and the negative electrode sheets each include a thin metal plate. An electrode tab extends from one edge of the thin metal plate. For example, refer to patent document 1.
In a rechargeable battery described in patent document 1, in each electrode sheet, an active material layer is formed on a surface of a thin metal plate although an active material layer is not formed on an electrode tab. The electrode tab is electrically connected to an external terminal (electrode terminal), which is formed outside a case, by a current collection terminal (current collection member). In the rechargeable battery described in patent document 1, the positive electrode sheets are smaller than the negative electrode sheets. This limits decreases in the battery capacity caused by an imbalance in the size of regions (electrode sheet) where the active material layers are formed.